When Hank the chimp was found dead Monday, his death brought to light a string of unexplained animal deaths that has put the Chattanooga Zoo at Warner Park under a microscope.
Not since the early 1980s, just before Friends of the Zoo was formed in reaction to concerns over poor conditions, has the zoo faced such intense scrutiny.
A number of improvements have been made since then, including new exhibits with more space and improved habitats. In the last decade alone, the zoo has more than doubled its acreage and increased the size of its animal collection.
But that means there's more to do and more to manage.
Hank, at 42, was the zoo's mascot, and his unexpected passing prompted a number of zoo critics and whistleblowers to charge that the zoo needs tighter management and oversight and has for years.
Some critics have said the best hope for that dimmed in September when Chattanooga contracted the zoo's management to the nonprofit Friends of the Zoo. The city paid the Friends $648,577 for the 2011 budget year and top management -- including zoo director Darde Long -- was carried over.
But with that change, a number of longtime zookeepers left to keep their city benefits and seniority or to work at other zoos.
Within weeks, animals began to die.
Hank was the seventh animal death at the zoo in a month's time, and the 10th since early November, according to zoo vet Tony Ashley. But preliminary forensic exams do not point to any clear connections.
"I can't speak to the animal husbandry at the zoo, only to medical care [and preliminary necropsies]," Ashley said Friday.
"So far it doesn't appear that any of the deaths are related," he said. "We wonder why this has happened, and we want answers. But [so far] you can't place the blame on anybody."
Probes and reviews
Groups are lining up to try, however.
PETA -- People for the Ethical Treatment of Animals -- has received a complaint about how animals are treated at the Chattanooga Zoo.
"We've heard from one whistleblower," said Debbie Leahy, PETA's director of captive animal rescue and enforcement.
With the PETA announcement, zoo spokeswoman Robin Derryberry released a statement from Friends of the Zoo Board President Gary Chazen.
* 1937: The Chattanooga zoo begins at Warner Park with two rhesus monkeys in a 4-foot by 6-foot cage.
* 1942: Collection grows to include lions, buffalo, alligators and bobcats.
* 1969: Plans are made to shift the zoo's focus to a petting zoo. "Zooville" opens with goats, sheep and other farm animals.
* 1970s: Zoo conditions deteriorate while larger zoos across the nation begin to shift toward natural habitat exhibits and conservation education.
* 1985: Public pushes for zoo to improve or close. Friends of the Zoo is formed to raise money for improvements.
* 1989: New master plan calls for an expansion to 50 acres.
* 1993: Plan is scaled down to 5 acres.
* 1998: Chattanooga Zoo receives first accreditation from the Association of Zoos and Aquariums, with reaccreditations in 2003 and 2008.
* 2000: Master plan is updated to 12 acres.
* 2001: Hank gets expansive new digs when Gombe Forest chimpanzee exhibit opens.
* 2004: First section of the Himalayan Passage opens featuring red pandas.
* 2005: Cougar exhibit opens.
* 2006: Himalayan Passage is complete, adding snow leopards and Hanuman langurs.
* 2008: Opening of $4.2 million entrance complex at western boundary of Warner Park with gift shop, ticketing area, concessions pavilion and carousel expands zoo footprint to 13 acres.
* 2010: In September, Chattanooga contracts zoo management to Friends of the Zoo.
Source: Chattanooga, Chattanooga Zoo at Warner Park
* A gecko died in November
* A tortoise died in December
* A male muntjac, an Asian deer, died in mid-December
* Two marmosets died in late December
* A tortoise died in early January
* A female muntjac died the second week of January
* Two snow leopard cubs died or were stillborn the second week in January
* Hank the chimpanzee was found dead Monday
Source: Chattanooga Zoo officials
"Our board takes this situation very seriously," Chazen said in the statement. "We are currently working with appropriate entities to determine the cause of death of these animals. This has been and will continue to be our top priority and focus until all questions have been answered."
Leahy said PETA, the world's largest animal rights organization, will watch what federal zoo regulators do in coming days and weeks.
David Sacks, a spokesman with the U.S. Department of Agriculture's Animal and Plant Health Inspection Service, confirmed shortly after Hank's death that USDA had received an anonymous complaint.
On Friday, Sacks said zoo director Long, who had invited USDA to make a new inspection, told him a USDA investigator already has begun that look.
The Association of Zoos and Aquariums, which accredits both the Chattanooga Zoo and the Tennessee Aquarium, has received two requests to look into the zoo's operation, a spokesman said.
One was from a member of the public, and the other was from the zoo itself, spokesman Steve Feldman said.
"This is a proactive step by the zoo to seek an independent review," Feldman said. "It's an example of how seriously the zoo takes this."
In March, the AZA plans its midyear meeting in Chattanooga, hosted by the zoo and the Tennessee Aquarium.
In all of 2010, the zoo lost 10 animals, said Derryberry, who also is a board member of Friends of the Zoo.
At least half were in November and December. Five more have died already in 2011.
Ashley said two tortoises and a gecko died in November, but have not been included in recent news accounts of zoo deaths.
The complaint to PETA details a number of other incidents.
Those include the deaths of two marmosets and a muntjac -- a small Asian deer -- that died after falling into a koi pond when it was locked out of its shelter for a Holiday Lights fundraising event. The muntjac was frightened by barking dogs and, in panic and disorientation, fell into the freezing pond, according to the complaint.
Another muntjac died within days, from what Ashley said was a twisted colon.
Ashley said he examined two dead snow leopard cubs shortly after their birth in early January, but could not confirm whether they were stillborn, as zoo officials have claimed, or whether they died from the cold.
Whistleblowers claimed the two cubs died after being born outside while the female snow leopard was locked outside her den. A third cub was born inside after her den was opened and so far has survived. It is gaining weight, Ashley said.
PETA's Leahy criticized the zoo's lock-out events and its policy of allowing visitors to bring in dogs.
"We're very concerned about animals being locked out [of shelter while] on display. They should never be locked out, especially on bitterly cold evenings," she said. "And we are troubled by reports that people were allowed to bring their dogs into the zoo, and the dogs were stressing out some of the animals."
Leahy said she also was concerned about scheduling mistakes that have been acknowledged by zoo officials.
Whistleblowers told the Times Free Press and PETA that the marmosets, a type of monkey, were without food and water for four or five days. Zoo officials have said it was only one day.
"Whether it was one day or four days, they're dead," Leahy said.
Ashley and Mickey Myers, a veterinarian and board member -- and Ashley's boss -- said the marmosets' preliminary necropsies indicate they had a type of hepatitis virus commonly carried by mice.
Leahy said PETA has no plans to protest at the zoo, although she said that could change if conditions don't improve.
"We have higher expectations for accredited zoos," she said, referring to the Chattanooga zoo's AZA membership.
Zoo officials have said that Chattanooga is among the 10 percent of the nation's zoos that have achieved AZA accreditation.
What about Hank?
Great apes like Hank have life spans not unlike people.
In the wild, many males that have to fight to survive die around age 35, according to experts, but most average about 20 more years of life in captivity. The longest-lived chimpanzee in captivity was 65.
Hank was 42 and had lived in captivity all his life. He was 7 when he came to the Chattanooga Zoo in 1976.
His former keeper, John Urstadt, said Hank was healthy when Urstadt left the zoo in May with plans to begin his own zoo in Florida. Urstadt is one of several former employees who told the Times Free Press that the transition from city management to Friends of the Zoo oversight left the facility short of keepers with large-animal handling experience.
The zoo director praised her new staff, saying her three newest hires have more education than the former workers and two have experience with large animals.
Myers said Hank had a physical in June, performed by veterinarian researchers at the University of Tennessee. They found Hank suffered from diabetes but showed no heart problems.
Ashley said the preliminary results from Hank's necropsy show he had fluid around his heart.
"When that happens the heart can't pump," Ashley said Friday.
Ashley said three things could have caused that: cancer, heart disease and infection.
He said Hank had no indication of cancer. He deemed heart disease a maybe, though none was seen in June and nothing in the preliminary necropsy "screams" heart failure. He said only the final necropsy can determine if infection was a culprit.
Mayor Ron Littlefield said last week that he and zoo officials have known Hank was sick "for a long time."
Of the other animal deaths, the mayor indicated he is taking a wait-and-see attitude.
"The number is interesting, but I don't think we need to rush in and wrench it away from them [Friends of the Zoo]," he said.
Staff writer Cliff Hightower contributed to this story. Contact Pam Sohn at email@example.com or 423-757-6346.